SAN FRANCSICO (KPIX 5) – San Francisco’s police chief confirmed in an interview Friday that one of the two teenage girls killed in the crash of a passenger jet at SFO was run over by an fire truck while she was hidden by foam sprayed by firefighters to extinguish the flaming wreckage.

Chief Greg Suhr told reporter Phil Matier during a live interview on KPIX 5 Friday that police investigators determined that 16-year-old Ye Meng Yuan was run over at least once by an emergency vehicle at the scene of the Asiana Flight 214 crash.

A police spokesman later clarified the vehicle was a fire truck.

However, Suhr said it was unclear whether the collision killed her. “At the time, she was under foam, so nobody could have seen her, and the question is whether or not she was still was alive at the time,” he said.

Initial probes into the possibility the girl was hit by a vehicle were inconclusive. On Tuesday, the San Francisco Police Department announced its thit-and-run unit would take over the investigation into the teenager’s death.

San Francisco fire spokeswoman Mindy Talmadge said the fire department is still conducting its own internal investigation, but acknowledged that police have confirmed that a fire truck ran over the girl.

Talmadge also said Friday that the second girl killed, 16-year-old Wang Lin Jia, was already dead when airport staff found her near a runway seawall along with three flight attendants who had been ejected from the back of the plane when it broke open. The flight attendants survived.

Suhr said the San Mateo County coroner would have to determine whether Yuan was already dead at the time of the collision with the emergency vehicle.

The two teenagers were part of a group of 29 students and five teachers from an affluent coastal province in eastern China heading to a summer camp run by a Southern California Christian church.

The Boeing 777 was carrying 291 passengers and 16 crew members when it crashed at San Francisco International Airport Saturday morning. Aside from the two girls killed, 180 other passengers were injured.